Adds --no-enum-size-warning and --no-wchar-size-warning to the list of
ignored args for lld. These are valid arguments to GNU ld for
ARM/AArch64, so for compatibility they are now accepted but just
ignored. If the functionality is ever desired, this can be revisited at
See https://sourceware.org/binutils/docs/ld/ARM.html for more on these
arguments for GNU ld.